Huntington Disease (HD) is a late onset neuropsychiatric disorder that is inherited in an autosomal dominant manner meaning that each child of an affected parent has a 50% chance of inheriting the genetic mutation that is known to cause HD. The symptoms include a movement disorder, cognitive decline leading to dementia and a variety of psychiatric disorders. In 1983, HD became the first disease mapped to a previously unknown location on chromosome 4 through the use of restriction enzymes. This discovery meant that some individuals at risk for HD could learn whether or not they would develop HD at some point in the future. Shortly thereafter, both the Huntington's Disease Society of America (HDSA) and the World Federation of Neurology, in concert with the International Huntington Association, published guidelines for predictive testing. Both sets of guidelines recommended that testing not be done on individuals younger than the age of 18. The goal of this prohibition against testing children was to preserve the autonomy of the at risk child to decide whether or not to be tested when he or she reached the age of majority. Despite these guidelines, children have been tested and testing in children is likely to increase in the future. Developmentally, this testing occurs at a time of great social, emotional, and cognitive change as individuals finish their education, enter the workforce, leave their families of origin and transition from first romantic and sexual relationships to more enduring partnerships. Genetic testing may interfere with these life cycle transitions but we know next to nothing about how these children and their families make the decision whether or not to be tested or how they cope with the results once testing has occurred. The goal of this study is to use a mixed methods approach and McAdams's life story model of identity to examine how adolescents and young adults at risk for HD integrate the reality of being at risk for HD and the decision whether or not to be tested into their life story. The secondary goal is to examine how individuals who have been tested integrate this new knowledge into their life story. PUBLIC HEALTH RELEVANCE: The goal of this project is to use a mixed methods approach and McAdams's life story model of identity to examine how adolescents and young adults at risk for Huntington Disease (HD) integrate the reality of being at risk for HD and the decision of whether or not to be tested into their life story. The secondary goal is to examine how individuals who have been tested integrate this new knowledge into their life story. The third goal is to examine whether the manner in which individuals who have been tested integrate this new knowledge into their life story affects their subsequent adjustment to test results.